The overall objective of the program is to establish the basic biochemical characteristics of major components of the insect microsomal enzyme system. It is hoped that through comparative studies with similar components of mammalian microsomes, differences might be uncovered which can be exploited in the more rational design and development of new insecticides showing greater selectivity. Specific aims include attempts to solubilize, purify and characterize the major catalytic components (NADPH cytochrome c reductase and cytochrome P-450) of control and induced armyworm (Spodoptera eridania) midgut microsomes, to study the role of DNA-dependent RNA polymerases in microsomal enzyme induction in the armyworm, and to solubilize and characterize the microsomal epoxide hydrase in the same species. In collaboration with researchers at Michigan State University, it is proposed to carry out cross-reconstitution studies (insects vs. mammals) with the purified components. Immunibiochemical studies are also in progress. BIBLIOGRAPHIC REFERENCES: Brattsten, L.B. and C.F. Wilkinson. 1977. Insecticide solvents: Interference with insecticide action. Science, in press. Gil, D.L. and C.F. Wilkinson. 1977. Structure-activity relationships of 1,2,3-benzothiadiazole insecticde synergists as inhibitors of microsomal oxidation. Pest Biochem. Physiol., in press.